The present invention relates in general to an adjustable orifice for emulsifier and, more particularly, to an adjustable orifice assembly adapted for use in an apparatus for homogenization of a stream of a liquid component and a substantially insoluble component which may be either a liquid or a finely divided solid by the use of cavitating flow.
In accordance with U.S. Pat. No. 4,127,332, there is disclosed a homogenization apparatus which provides an emulsion or colloidal suspension having an extremely long separation half-life by the use of cavitating flow. The prior art homogenization apparatus is constructed of a generally cylindrical conduit including an orifice plate assembly extending transversely thereacross and having an orifice opening provided therein. The orifice opening is described as embodying various designs such as circular blunt or sharp edged, square sharp edged and, a pair of substantially semi-circular annular segments. The homogenization process is effected by passing a multicomponent stream, including a liquid and at least one insoluble component, into a cavitating free turbulent velocity shear layer created by the orifice opening through which the stream flows with a high velocity. The cavitating free turbulent shear layer provides a flow regime in which vapor bubbles form, expand, contract and ultimately collapse. By subsequently exposing the free turbulent shear layer to a sufficient high downstream pressure, the bubbles collapse violently and cause extremely high pressure shocks which cause intermittent intermixing of the multicomponent stream. As a result, a homogenized effluent of liquid and the insoluble component is generated which has a substantially improved separation half-life.
In accordance with the prior art homogenization apparatus, it is generally known that the effective intermixing of the multicomponent stream is dependent upon a number of factors, for example, upstream pressure, downstream pressure, conduit diameter, orifice diameter, etc. The most critical factor is generally considered to be the orifice diameter, which factor is often the most difficult to control effectively over the continued use of the homogenization apparatus. Specifically, upon heating of the orifice plate assembly, the resulting expansion causes variation in the orifice diameter thereby adversely effecting the homogenization process. Further, erosion of the orifice plate assembly at the orifice opening due to chemical or mechanical action caused by the insoluble particles within the multicomponent stream, causes the orifice diameter to increase during the homogenization process also resulting in a change in the effectiveness of the intermixing of the multicomponent stream. Still further, it is generally required that the orifice diameter be determined for each different homogenization process, which determination is generally extensive in labor, in addition, to requiring system shutdown during installation of a different orifice plate assembly.
Thus, it can be appreciated that there is an unsolved need for an orifice plate assembly adapted for use in a homogenization apparatus which provides for the effective intermixing of a multicomponent stream in a potentially corrosive environment over a variety of operating conditions in an economical and effective manner.